Straightedge



April 6, 1937. A. J. A cRolx Filed July 18, 1955 (m\ um ally is of channel or angle formation.

Patented Apr. 6, 1937 UNITED STATES PATENT (JFFICE STRAIGHTEDGE Application July 18, 1935, Serial No. 32,027

7 Claims.

My invention relates more especially to a wall paper trimmers straightedge and has to do with the metallic binding strips and the manner of securing the same in place so as to provide a smooth uninterrupted outer surface for the trimming tool or paper cutter during its travel longitudinally of the straightedge.

Straightedges made of wood require the longitudinal edges to be provided with metallic protective elements, generally brass strips of channel formation and adapted to extend from end to end of the straightedge, with the side of one of the channel strips adapted to provide a trackway for the guide member of the paper trimming tool.

The invention has for its object the provision of means so associated with the metal edging or binding strips that the fastening means will be entirely located on the straightedge side of the binding strip and will effect holding or fastening relation with the body of the straightedge without fracturing the latter and at the same time will maintain the proper holding relation regardless of any shrinking or warping of the body of the straightedge.

A further object of the invention is to provide a construction which may be easily made and assembled and the metal edging strips securely held in place against accidental removal or from becoming loose.

The aforementioned objectsk and advantages, as well as other advantages inherent in the construction, will be readily comprehended from the following detailed description of the accompanying drawing, wherein:-

Figure 1 is a sectional perspective view of a straightedge embodying my invention.

Figure 2 is a longitudinal sectional View taken substantially along the line 2-2 of Figure l,

' looking in the direction of the arrows.

- Figure 3 is a detail perspective View of one of the metal edging fastening means.

Figure 4 is a perspective view of a modified form of a screw-holding clip or plate.

` Figure 5 is a perspective view of another modified form of clip or plate.

Straightedges made of wood, or a suitable libre, require the longitudinal edges to be provided with a metallic protective element or strip, which usu- These metallic strips have heretofore generally been secured to the body of the straightedge by means of screws driven through spaced ap-art holes in the strips along the longitudinal sides of the straightedge.

In practice it has been found that the screws would become more or less loose and have a tendency to back-out or unscrew; a condition not always readily noticeable.` As a result the trimmer blade Would make Contact with the slightly 5 protruding head of the screw and consequently damage the blade. Damage and dulling of the blade also has resulted from small metal burrs on the screw-heads or in the countersink for the screw-heads in the metal strips and produced by l the action of a screw-driver.

The invention contemplates a construction wherein the objectionable conditions just enumerated will not be present; and in the specific i embodiment, the body portion of the straightl5 edge is made of laminated wood to provide a straightedge of desired width and length. The upper surface of the body portion 5 slightly removed from one of the longitudinal edges is longitudinally grooved at 6 to provide clearance for 20 the guide element on the trimmer.

The longitudinal edges of the straightedge are provided with metallic channel members 1, 1, disposed throughout the entire length of the straightedge.

These metal channel members are adapted to receive the longitudinal edges of the main body 5 with the sides of the channel members arranged in lapping relation with the upper and the lower faces of the main body portion 5.

One of the sides of each channel member is shown of greater width than the other (although both sides may be of equal width) and the wide side preferably overlaps the upper face of the straightedge; and hence the wide side of channel member 'l will overhang a portion of the groove 6 in the body 5, and enable it to act as a guide when a trimming tool is used.

Both sides of the channel members, adjacent the base of the channel, are provided with a 40 slot or small groove 8 which preferably extends throughout the lengthA of each side of the channel members l, as shown in Figure 2.

The grooves 8, 8 are adapted to receive the longitudinal edges of the holding plates or washers 9, shown in detail in Figure 3. The plates or washers 9, intermediate of the ends, are apertured for passage of the threaded portion of the screws I0 therethrough and permit free rotary movement of the screws. The apertures in the plates or washers 9 are countersunk as shown at I l so as to receive the heads of the screws lll as shown in Figures 1 and 2 at I2; the displaced metal around the apertures forming the cup-like portion shown in Figure 3 on one side of the 55 washer in which the head of the screwl will seat so as to be flush with the outer side of the washer while giving the screw free play.

The screw Ii) is preferably provided with a quick 5 thread to induce it to screw into the wood body 5 of the straightedge when the head of the screw is subjected to pressure or blows; such rotating or screwing movement being possible by reason of the loose fit between the screw and the washer.

l It is apparent that with the longitudinal edges of the plate or washer 9 arranged in the slideway produced by the opposing grooves 8, 8, the metal strips 'l will be secured to the longitudinal edges of the main body of the straightedge; a suitable l number of the composite holding elements Q-l being used, spaced apart longitudinally of the straightedge.

In practice, the composite holding elements or fastening means S-i are first applied to the longitudinal edges of the main body of the straightedge by driving the screws lil into the fibre or wood to such an extent that the plate or washer S will be held against rotation on the screw, namely to the point where the cupped countersunk portion l! will engage the body 5 of the straightedge and hold the washer il in position with its longitudinal edges extending parallel with the longitudinal edges of the body 5, while at the same time permitting suiiicient play of the washer to enable it to freely enter the slots or grooves 8, 8 from one end of the channel binding strips l.

The washers 9 are preferably made slightly wider than the thickness of the main body 5 of the straightedge so as to permit the longitudinal edges of the washers to extend into the slots or grooves 8, 3 at opposite sides of the channel binding strips 'i as shown in Figure l.

After the fastening means, consisting of elements 9 and l) have been applied to the main body 5 as above stated, the binding strips are then endwisely applied to the straightedge with the sides of the channel strips disposed toward the body 5 and the ends of the grooves 8, 8 arranged to register with the longitudinal sides of the plates or washers 9. The binding strips l are slid lengthwise of the body 5, in interlocking ree lation with each plate or washer 9, until the ends of the binding strips are iiush with the ends of the body portion 5. The strips are then subjected to slight blows or pressure, at points substantially coincident with the washer carrying screws, which will completely drive the screws into the body portion 5 and firmly hold the metal edging in place against accidental movement; the cupped 55 portions l l of the washers becoming embedded in the body portion 5 as shown.

In order to obviate any possibility of the edging or binding strips l moving lengthwise .of the straightedges through some improper handling, I

60 prefer to employ at each end of the straightedge the type of washer or clip i4 shown in Figure 4. This clip or washer H, which is preferably made of tempered steel, has one end slightly bent and ground to a chisel edge as at l5; this edge being 65 disposed toward the opposite side of the clip provided with the cupped or screw-head received portion Il. That is to say, the bent sharp edge l5 is intended to be disposed toward the base of the channel strip 7; and as these clips are preferably tempered the sharp edge I5 will bite into the brass channel.

With this construction accidental travel or movement of the channel strips lengthwise of the straightedge is made impossible.

In practice, clips like that heretofore described and shown in Figure 3 are applied intermediate of the ends of the straightedge, either by using the ordinary wood-screw or a quick-thread screw, and a clip like it is secured adjacent one end of the straightedge; these clips being secured to the body of the straightedge so as to permit the longitudinal edges of the clips to enter the grooves or slots 8 in the channels. The channel is driven along the edge of the body of the straightedge toward the opposite end which is then provided with a clip like that shown in Figure 4 and the channel l then driven into place with its ends flush with the ends of the body portion. The channel may then be subjected to blows or pressure in alignment with the clips and screws thereby causing the screws to completely enter the wood or fibre.

In order that the channels may be flush with the longitudinal edges of the body of the straightedge, I prefer to provide the body with cut-out portions or valleys of depth commensurate with the thickness of the clips as shown in Figure 2.

When the channels 'l are subjected to pressure or blows coincident with the clips and screws, the sharp ends i5 of the end clips will be caused to bite into the soft brass channels and effect the hol-ding relation mentioned.

In Figure 5 I illustrate another modification of the clips. rI'he clip I6, like clip 9, may be composed of untempered metal, cut to preselected length and provided centrally with a screw receiving opening which preferably is countersunk so that the screw-head may extend flush with the outer surface of the clip.

The clip i6 is shown slightly dished transversely and normally intended to have its longitudinal edges l'l, Il enter the grooves 8, 8 in the side walls of the channel, with the convexed side of the clip disposed toward the base of the channel.

After the screws and clips with the channel strips have been applied, the channel strips are then subjected to further pressure or blows, particularly at points coincident with the screws and clips, which will cause the untempered clips I6 to atten or straighten out which induces the longitudinal edges il', Il of the clips to move laterally into rm binding relation with the bottoms of the grooves 8, 8 in the channel strips.

It is apparent that with my improved methods of fastening, a straightedge is provided whose metal binding strips are imperforate and hence the straightedge will have smooth uninterrupted surfaces, oifering no obstruction to the keen edge of the trimmers knife or trimming tool. The binding strips of straightedges generally consist of comparatively soft metal such as brass with the result that where the strips are fastened by screws passing through the strips, the use of a screw-driver frequently causes the formation of small burrs at the screw-holes and these burrs contact with the edge of the blade drawn along the straightedge interfering with proper trimming operation and dulling the trimmer,

With my improved method of Securing the metal binding strips, these difficulties and objectionable features are all obviated and the metal binding strips are provided with smooth uninterrupted outer surfaces; and while the exemplifications shown in the drawing are believed the best embodiments of the invention certain modifications may be made without departing from the spirit of my invention as expressed in the appended claims.

1. A straightedge of the character described comprising a iibrous body portion; imperforate metal strips disposed along the longitudinal edges; bre penetrating elements arranged at preselected points lengthwise of the body portion; and means intermediate of the metal strips and the outer ends of the elements whereby holding relation between the strips and said elements is effected.

2. A straightedge of the character described comprising a wood body; imperforate channel metal strips disposed along the longitudinal sides; screw carrying elements arranged within the channel strips and in gripping relation therewith whereby the metal strips are secured to the sides of the body of the straightedge; and a wood screw disposed through each element and screwed into the wood body.

3. A straightedge of the character described comprising a main body portion; imperforate metal channel strips extending throughout the ,longitudinal sides of the body portion, the inner side walls of the channel having opposing grooves; screw carrying washers whose edges fit into said grooves; and body portion penetrating screws disposed through the washers.

4. A straightedge of the character described comprising a brous body portion; channel strips arranged along the longitudinal edges of the body portion; body portion penetrating elements; and rigid means adapted to effect interengaging relation with the inner surfaces of said strips and arranged in holding engagement with said elements.

5. A straightedge of the character described comprising a main body portion; imperforate metal channel strips extending lengthwise of the longitudinal sides of the body portion, the inner side walls of the channels adjacent the base having opposing grooves; apertured metal washers of width substantially equal to the distance between the bottoms of the opposing grooves arranged with their longitudinal edges disposed in said grooves, said washers being arranged in binding engagement with the channel; and a screw disposed through the aperture in each washer and screwed into the body portion.

6. A straightedge of the character described comprising a fibrous body; imperforate metal strips disposed along the longitudinal sides of the body; body penetrating elements arranged at preselected points lengthwise of the body; and means secured to the body penetrating elements adapted to eiect a frictional inter-engaging relation with the strips and thereby hold the latter in place.

7. A straightedge of the character described comprising a body portion; metal strips arranged along the longitudinal edges of the body portion; body penetrating elements inserted into the longitudinal edges of the body portion at spaced apart points; a-nd means secured to each element and arranged in holding relation with the inner faces of the metal strips to thereby secure the strips on the longitudinal edges of the body portion.

1 ARTHUR J.. LA CROIX. 

